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TB Notes 1, 2000
Where We've Been and Where We're Going: Perspectives from CDC's Partners in TB Control
Changes I've Seen
TB Control in New York City: A Recent History
Not by DOT Alone
Baltimore at the New Millennium
From Crickets to Condoms and Beyond
The Denver TB Program: Opportunity, Creativity, Persistence, and Luck
National Jewish: The 100-Year War Against TB
Earthquakes, Population Growth, and TB in Los Angeles County
TB in Alaska
CDC and the American Lung Association/ American Thoracic Society: an Enduring Public/Private Partnership
The Unusual Suspects
The Model TB Prevention and Control Centers: History and Purpose
My Perspective on TB Control over the Past Two to Three Decades
History of the IUATLD
Thoughts about the Future of TB Control in the United States
Where We've Been and Where We're Going: Perspectives from CDC
Early History of the CDC TB Division, 1944-1985
CDC Funding for TB Prevention and Control
Managed Care and TB Control - A New Era
Early Research Activities of the TB Control Division
The First TB Drug Clinical Trials
Current TB Drug Trials: The Tuberculosis Trials Consortium (TBTC)
TB Communications and Education
TB Control in the Information Age
Field Services Activities
TB's Public Health Heroes
Infection Control Issues
A Decade of Notable TB Outbreaks: A Selected Review
International Activities
The Role of CDC's Division of Quarantine in the Fight Against TB in the U.S.
The STOP TB Initiative, A Global Partnership
Seize the Moment - Personal Reflections
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This is an archived document. The links are no longer being updated.

TB Notes 1, 2000

The Role of CDC's Division of Quarantine in the Fight Against TB in the US

by Paul Tribble
Public Health Advisor, DQ

The Division of Quarantine (DQ), the oldest organization in the United States Public Health Service, has had a rich and colorful history and plays an important role in the nation's fight against tuberculosis (TB), especially with respect to immigrants and refugees. DQ, which was established by the National Quarantine Act of 1878, was transferred to the Centers for Disease Control (CDC) in 1967. DQ has had several previous titles, including the Division of Foreign Quarantine and Quarantine Division, and is continuing to evolve with another proposed name: the Division of Global Migration and Quarantine.

Image 1: Immigrants of the past awaiting medical clearance.

United States (US) immigration law mandates an overseas health assessment for immigrants and refugees, with the intent of denying admission to persons with certain diseases of public health significance, physical or mental disorders associated with harmful behavior, drug abuse or addiction, or likelihood of becoming a ward of the state. The conditions, the requirements as to who must be screened, and the examination and tests to be performed are prescribed by the Secretary of the Department of Health and Human Services, with oversight by DQ.

The current list of communicable diseases of public health significance that are considered "inadmissible" are infectious TB, syphilis, lepromatous Hansen's disease, HIV infection, and certain sexually transmitted diseases (STDs). The overseas health assessment, which is valid for 12 months, is carried out by local physicians known as "panel physicians," who are appointed by the US embassy or consulate. In some cases, clinics or hospitals are designated as panel physicians in countries where large numbers of immigrants originate (e.g., Mexico, the Philippines, and Viet Nam). Panel physicians are provided with a booklet of technical instructions concerning the assessment process which, in addition to the TB evaluation, consists of a medical history, physical examination, and screening for physical and mental disorders, substance abuse, STDs, Hansen's disease, and HIV infection.

Panel physicians make their own arrangements for the required radiologic and laboratory tests. Currently, no countries have on-site supervision beyond the local consular officer, except Viet Nam, which has a CDC microbiologist consultant. Panel physicians do, however, receive periodic visits by CDC physicians and microbiologists based in Atlanta. Panel physicians are paid for their services by immigrant applicants on the basis of a fee scale set locally. In the case of refugees, the US Department of State reimburses the panel physicians for providing the health assessment. Presently, there are approximately 650 panel physicians worldwide.

The TB component of the health assessment consists of a chest x-ray for all persons 15 years of age or older. (Children less than 15 years of age who are suspected of having TB or who have a history of contact with a known TB case are given a tuberculin skin test. Those with a positive skin test must undergo a chest x-ray.) If the x-ray is consistent with active TB disease, three consecutive early-morning sputum specimens are collected for acid-fast staining and microscopic examination. Persons whose sputum smears are positive for acid-fast bacilli (AFB) are classified as having Class A, infectious TB, which is an inadmissible condition for purpose of entry into the United States. Such persons may enter the United States by meeting either of the following two conditions. First, sputum smear–positive immigrants and refugees who successfully complete a recommended course of TB treatment overseas can be medically cleared for US travel; they will have been reclassified as having Class B2 or old, healed TB (see description of TB classifications below). Secondly, they may enter the United States with a medical waiver, once they are no longer infectious, by providing three consecutive negative sputum smears. To obtain a medical waiver, the US relative of the Class A immigrant must complete an application. This is signed by a US health-care provider and is countersigned by the local health department (or signed only by the local health department acting as the health-care provider) at the immigrant's intended US destination, thus guaranteeing that the provider will assume responsibility for the completion of TB treatment. Class A refugees with TB are not required to have a relative residing in the United States, as the waiver is completed by the resettlement agency at the intended site of destination. Immigrants are responsible for paying for their own TB treatment overseas; in the case of refugees, the costs are assumed by the US Department of State.

Applicants whose chest x-ray is consistent with active TB disease but whose three sputum smears are negative for AFB are designated as having Class B1 (clinically active, not infectious) TB. If the initial chest x-ray is read by the panel physician as consistent with old, healed TB, no specimens of sputum need be obtained, and the applicant is designated as having Class B2 (not clinically active, not infectious) TB. Both Class B1 and B2 designations are considered significant health conditions, but neither is inadmissible for immigration purposes.

Image 2: Picture of the current immigration clearance process.

Class A and Class B designations for immigrants are placed on the official immigration documents collected by inspectors of the Immigration and Naturalization Service at one of 295 international airports, land crossings, or ports in the United States; refugees must enter the country through one of eight international airports that are staffed by DQ inspectors. This information is sent to or collected at one of the quarantine stations, where a notification form is mailed to the state or local health department at the intended destination of the arriving immigrant or refugee. Health departments are expected to complete and return the forms to DQ, thus reporting on the outcome of the evaluation. The immigrant or refugee is informed of the need to be further evaluated for their TB and to report to the local health department as soon as possible after arrival. Persons with Class A TB are required to report to the local health department, present all medical records and chest x-rays from overseas, and submit to the necessary testing, isolation, and treatment until discharged. They risk deportation should they fail to do so. For persons having Class B1 or B2 TB, the health department visit is considered voluntary.

Many health departments in the United States perform active follow-up of arrivals designated as having Class B1 or B2 TB, on the basis of the DQ notification. Studies conducted in the mid-1990s by the Division of TB Elimination, DQ, and health departments in various parts of the country have shown from 3% to 14% of Class B1 immigrants and refugees were diagnosed with TB disease within one year of their arrival; between 0.4% to 4.0% of those with Class B2 TB were diagnosed with TB disease within one year of arrival. Of the remaining persons, many are high-priority candidates for preventive therapy regardless of their age because they are tuberculin skin test positive with an abnormal chest x-ray suggestive of TB disease.

The current overseas TB evaluation procedures described above are based upon the following three principles: 1) the requirements apply specifically to immigrants and refugees, as they are most likely to become permanent US residents; 2) the procedures reduce the importation of active infectious TB that poses an immediate public health risk by denying admission to persons who have positive sputum smears; and 3) they allow those persons with evidence of TB disease but whose smears are negative to enter the United States, where a more complete medical evaluation can be performed and appropriate treatment can be provided under supervision. Forcing immigrants and refugees with noninfectious TB to undergo treatment overseas could prove to be counter-productive, as it may be difficult to ensure that the drug regimens are adequate, and that applicants are regularly ingesting the required medications. In such a scenario, incomplete treatment as well as development of drug resistance may be the result.

The overseas screening process for identifying and treating TB in immigrants and refugees is responsible for the identification of substantial numbers of persons arriving in the United States who have active TB. However, not all cases in newly arrived immigrants or refugees were identified overseas as having suspect TB, which is in part due to several limitations of the screening process. Although panel physicians do function under a contractual agreement with their respective US consulates, they receive no formal training or certification per se. In 1997, a training needs assessment was performed on a sample of panel physicians in a study undertaken by the Division of TB Elimination and DQ. The assessment indicated that, although 98% of panel physicians in the sample understood which immigrants and refugees should receive a chest x-ray, over 60% indicated a need for training.

Presently, efforts are underway to develop self-study training materials for panel physicians to enhance their ability to diagnose and treat TB, and to improve their ability to monitor the performance of contracted laboratory and radiologic services. A training plan will be developed, and self-study materials will be pilot-tested later this year in countries with large numbers of persons who immigrate to the United States and have a high TB prevalence.


Released October 2008
Centers for Disease Control and Prevention
National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention
Division of Tuberculosis Elimination -

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